5-azidocarbonyl pyrazinamide



United States Patent 3,094,530 S-AZIDOCARBONYL PYRAZINAMIDE Humphrey I.X. Mager, 34 de Ruyterstraat, Leidschendam,

Netherlands; Wouter Berends, 5A Kanaalweg, Delft,

Netherlands; and Willem J. Schut, 6 Tulpencroftlaan,

Heiloo, Netherlands N0 Drawing. Filed Feb. 1, 1961, Ser. No. 86,294 1Claim. (Cl. 2602-50) The present invention relates to new and novelderivartives of pyrazine 2,5-dicarboxylic acid and relates moreparticularly to compounds of the following formula:

u HiNii N wherein R is a hydrazine or azido group. These compounds areuseful as analeptics and as intermediates in the production of othercompounds containing a pyrazine nucleus.

In our application entitled Substituted Pyrazine Dicarboxylic AcidDerivatives, Ser. No. 86,295, we have described the preparation of Zcarbamoyl-S-(lower allcoxy)carbonylpyrazines of the formula:

3,094,530 Patented June 18, 1963 In order further to illustrate thisinvention but 'without being limited thereto, the following examples areincluded:

Example I A quantity of 1.56 g. (0.008 mol) 2-carbamoyl-5-ethoxycarbonylpyrazine and ml. 99% ethanol are heated .to boiling and1.8 m1. hydrazine hydrate are added to the boiling solution. The mixtureis refluxed with stirring for 5 minutes and allowed to cool to 5 C.

The yellow precipitate is recovered by filtration, washed three timeswith 10 ml. portions of 96% ethanol and dried in a vacuum desiccatorover phosphorous pentoxid'e. Yield: 1.44 g.(99%).

A mg. sample is recrystallized from 20 ml. Water to yield pureZ-carbamolypyrazine S-carboxyhydrazide as yellow needles, melting point299299.5 C. (dec.).

Example II 3.2 g. sodium nitrite is dissolved in 25 ml. water and to thesolution is added 1.44 g. 2-carbamoylpyrazine 5- carboxyhydrazide. Thesuspension is cooled in an icesalt bath and 16 ml. 5 N HCl are addeddropwise, with stirring, while the temperature of the mixture ismaintained between 0 C. and 5 C. After the addition of HCl is complete,the then colorless mixture is stirred for 10 minutes.

The White flocculent precipitate is filtered oif, washed 4 times with 10ml. portions of ice-cold water until free of chloride ions and finallyis dried in a vacuum desiccator over concentrated H 80 and pellets ofKOH.

Yield: 1.40 g. (91%) of Z-carbamoylpyrazine S-earboxylic acid azide.

It is understood that the foregoing detailed description is given merelyby way of illustration and that many variations may be made thereinwithout departing irom the spirit of our invention.

Having described our invention, what we desire to secure by LettersPatent is:

\2-carbamoyl'pyrazine S-carboxylic acid azide.

OTHER REFERENCES Spoerri et al.: J. Amer. Chem. Soc., vol. 60 (1938),pages 400-2.

